Commonly owned U.S. Pat. No. 6,558,365 to Zinger et al. illustrates and describes a fluid transfer assembly including a pair of initially inter-engaged vial adapters for use with a pair of vials for liquid drug reconstitution and administration purposes. Such fluid transfer assemblies are commercially available under the registered trademark MIX2VIAL® from the present Applicant Medimop Medical Projects Ltd., Ra'anana, Israel. The pair of vial adapters includes a vial adapter including a female connector referred to hereinafter as a “female vial adapter” and another vial adapter including a male connector referred to hereinafter as a “male vial adapter”. The male and female connectors are Luer connectors and preferably Luer lock connectors. The vials typically include one vial containing diluent and another vial containing a powdered drug medicament under vacuum. Typical vial sizes include 13 mm neck diameter and 20 mm neck diameter.
Liquid drug reconstitution and administration starting from an initial assembled configuration of a fluid transfer assembly includes the steps of:
(a) holding the diluent containing vial on a flat surface and downwardly snap fitting the male vial adapter thereonto;
(b) inverting the fluid transfer assembly to hold the fluid transfer assembly upright with the male vial adapter and its connected diluent containing vial above the female vial adapter;
(c) holding the medicament containing vial on a flat surface and downwardly snap fitting the female vial adapter thereonto whereupon the prevailing vacuum in the medicament containing vial rapidly draws the diluent from the diluent containing vial thereinto to form a reconstituted liquid drug and leaves a residual vacuum in the sealed assemblage of the fluid transfer assembly and two connected vials;
(d) gently agitating the sealed assemblage of the fluid transfer assembly and the two connected vials to fully reconstitute the liquid drug medicament in the vial connected to the female vial adapter;
(e) detaching the male vial adapter from the female vial adapter by unscrewing the male Luer lock connector from the female Luer connector;
(f) screw threading a syringe with a male Luer lock connector onto the female vial adapter;
(g) inverting the female vial adapter and its connected vial for aspirating the reconstituted liquid drug into the syringe; and
(h) unscrewing the syringe from the female vial adapter, attaching a needleand administering the reconstituted liquid drug.
Steps (a) to (d) are performed under sterile conditions but step (e) draws ambient air into the vial connected to the female vial adapter via its female connector to equalize the negative pressure therein. Ambient air particularly in outpatient clinics, hospitals, and the like, may be septic and therefore contaminate reconstituted liquid drug contents. Moreover, in some circumstances, female vial adapters are prepared in advance of immediate use and left standing for subsequent use thereby leaving their reconstituted liquid drug contents exposed to ambient air.